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donjahner1
28-04-2007, 02:52 AM
i am trying to find the formula for this problem, I have the wet and dry bulb return temps and the dry bulb unit outlet temp, how do i find the wetbulb outlet temp. I am new to forum, have 30 yrs in powerplant operations, last 18 at Ford motor co. Thought i would try and learn the other side. Thanks Don.

lana
28-04-2007, 04:29 AM
Hi Don,

How come you have the outlet dry bulb? Did you measure it?
Either you have to measure it or you have to do a coil calculation. This means you have to know your evaporator coil's physical info and then simulate the performance of the coil, this will give the outlet dry and wet bulb temperatures.

If you want to measure it then you can measure the outlet dry bulb temp. and relative humidity. With these you can calculate the wet bulb (with psychometric calculations or software).

Hope this help.
Cheers

Dan
28-04-2007, 04:48 AM
i am trying to find the formula for this problem, I have the wet and Dry bulb return temps and the Dry bulb unit outlet temp, how do i find the wetbulb outlet temp. I am new to forum, have 30 yrs in powerplant operations, last 18 at Ford motor co. Thought i would try and learn the other side. Thanks Don.

The wet bulb outlet temperature is simply a measurement you have to make just like you did with the return air. After that you can caculate your work performed. Oh. There I go, thinking like you are actually measuring these things.

Is it possible that you are asking how to read tables? Perhaps Lana is more on target with her answer.

donjahner1
29-04-2007, 08:46 PM
WOW A psychometric calculator, Thats what i needed. Told ya i was a begineer, Thanks.

Brian_UK
29-04-2007, 09:00 PM
Try here for software..

http://www.linric.com

lana
02-05-2007, 05:58 PM
Hi,

you can try this :
http://fridgetech.com/calculators/rel-hum-b.html

it is free.

Cheers